Machine for pressing plastic material.



APPLIOATION FILED DEO.14, 1909.

Patented Feb. 21, 1911.

3 SHEETS SHEBT 1.

A. B. KLAY. 4 MAGHINE FOR PRESSING PLASTIC MATERIAL.

APPLIOATION FILED D110. 14, 1909.

Patented Feb. 21, 1911.

3 SHEETS-SHBET 2.

UNITED STATES PATNT QFFTQE.

ABRAHAM B. KLAY, OF EAST SPARTA, OHIO.

MACHINE FOR PRESSING PLASTIC MATERIAL.

To all whom "it may concern:

Be it known that I, ABRAHAM B. KLAY, a citizen of the United States, residing at East Sparta, in the county of Stark and State of Ohio, have invented new and useful Improvements in Machines for Pressing Plastic Material, of which the following is a specification.

This invention relates to new and useful improvements in machines for pressing plastic material and its special object is to improve the construction and operation of machines of that general type which comprehends broadly a platen carrier and a pressing die, these elements having a relative approaching movement as a consequence of which the finished article is produced. An example of such a type of machine is illustrated in my prior Patent No. 687,688, granted November 26, 1901.

An embodiment of the invention herein disclosed by way of example, is illustrated in the accompanying drawings and explained with particularity in the following description.

In the drawings: Figure 1 is a sectional view of a machine in which the present improvements are incorporated. Fig. 2 is a side elevation thereof. Fig. 3 is a front elevation thereof. Fig. 1 is a detail longitudinal sectional view of an improved feeding device. Fig. 5 is a detail cross sectional view of the device. Fig. 6 is a detail cross section of an adjustable plate and its adj uncts, forming parts of the feeding device. Fig. 7 is an end elevation of the plate. Fig. 8 is a top plan view of the feeding device. Fig. 9 is a top plan View of an improved die box. Fig. 10 is a cross section on the line 10-10 of Fig. 9. Fig 11 is a detail perspective view of an adjustable element of the die box. Fig. 12 is a side elevation of a cam forming a. part of novel die cont-rolling mechanism. Fig. 13 is a detail view of a connecting link between the feeding device and its operating means. Fig. 1 1 is a detail view of a flange which is carried by an adjustable part.

Similar characters of reference designate correspoi'iding parts throughout the several views.

Before taking up with particularity the improvements which form the subject of the present invention, it will be necessary to describe briefly the general construction and operation of the machine in which the im- Specification of Letters Patent.

Application filed December 14, 1909.

Patented Feb. 21, 1911.

Serial N0. 533,092.

provements are incorporated. As an example of such a machine there has been selected the construction shown in my prior Patent No. 687,688, referred to. This machine includes frame standards 1, 2 and 3, which support an intermittently revoluble platen drum carrying the lower dies, and mechanism for reciprocating the upper die.

The platen drum is designated generally by the numeral 4: and is advantageously of pentagonal form.

The lower dies, designated generally by the numeral 5, are assembled with relation ,to the flat faces of the drum. There are accordingly five lower dies, and these, as a consequence of the intermittent rotation of the drum, have a traversing movement with respect to the upper or pressing die. The latter is designated by the numeral 6, and is mounted upon a cross head 7 which slides vertically between guides 8 which are se cured to the standards 1 and 2. The vertical sliding movement of the cross head is advantageously produced by a toggle system, which includes links 9 that are secured to the cross head 7, links 10 that are secured to a relatively stationary transverse beam 11, and a bar 12 which is pivotally connected to the mutually adjacent ends of the links 9 and 10.

The main drive shaft is designated by the numeral 13 and is connected in any suitable manner with the source of driving power. The means for operating the platen drum from the shaft 13 as shown, is the same as in my patent referred to and comprises the following elements. The shaft 13 is provided with pinions 14, which mesh with larger pinions 15 that are provided on a countershaft 16. The latter is provided also with a mutilated gear 17 and an escape wheel 18. The shaft upon which the platen drum is mounted is designated by the numeral 19 and is provided with a spur gear 20, with which the mutilated gear 17 meshes at intervals, and with a star wheel 21, the teeth of which successively project into a peripheral recess in the escape wheel 18, the recess being provided to allow of the intermittent partial rotations of the shaft 19. The foregoing driving elements are only referred to in a general way, since their construction and operation is clearly disclosed and explained in the patent referred to.

The operation of the toggle system above mentioned, is effected by the reciprocations of a cam bar 22 which is driven in the manner specifically set forth in my patent and to the upper end of which is attached a link as 23. At the upper end of the standard 3 a block, as 24, is mounted and to this block there is pivoted a link, as 25,the latter being also pivoted to the end of the link 23. The pivot of the links 25 and 23 is also the pivot of a link 26, which is in turn connected to the bar 12. It will be apparent that the links 23, 25 and 26 constitute a toggle system which in turn produces the operation of the toggle system constituted of the links 9 and 10.

The description thus far given relates to a construction that is known in the art. Such description, however, is not intended to place any specific limitations upon the character or construction of the known elements of the novel combinations which the invention presents but it is to be regarded simply in the light of example.

The present invention involves, inter alia, a novel construction of the lower dies, by means of which the finished article is produced in a highly eiiicient manner and is of superior quality while at the same time a number of mechanisms heretofore employed and necessary to produce a perfectly finished article, are rendered unnecessary. Each lower die 5 consists essentially of a rectangular frame, as 27, which is secured to a flat face of the platen drum, and which has the inner faces of its walls inclined taperingly in an outward direction, as shown more particularly in Figs. 1 and 10. WVithin the frame 27 there is assembled what may for convenience be termed a die box and which consists of separable wall members, as 28. The members 28 have their outer faces inclined conformably to the respectively adjacent inner faces of the frame 27 and their inner faces disposed perpendicularly with relation to the adjacent flat face of the drum 9. The members 28 are radially and adjustably movable with relation to the drum and accordingly they are articulated with the adjacent walls of the frame 27 in a suitable manner for this purpose, preferably by dovetail connections embodying ribs, as 29, which are formed on the inclined faces of the members 28 and which conformably engage in dovetail recesses in the walls of the frame 27. To effect the aforesaid radial movement of the members 28, adjusting screws, as 30, are preferably employed. The screws 30 are fitted loosely in concave smooth -surfaced recesses 31 which are formed centrally in the inner faces of the frame 27 and they have threaded engagement in concave recesses 32 which are formed in the inclined faces of the members 28, as shown more particularly in Figs. 10 and 11. To hold the screws 30 against axial play, flanges, as 33, are provided near the upper ends thereof, which project into recesses in the walls of the frame 27. To the inner faces of the members 28 are secured lining plates as 34. The plates 34L havesuitably arranged horizontal slots 35 through which extend the screws or other fastenings 36 for holding said plates in position. By assembling the plates in this manner a limited horizontal play thereof is provided for. The plates 34 are arranged with their ends in overlapping relation for a purpose which will presently appear.

By virtue of the relation of the inclined faces of the frame 27 and the members 28 it follows that as the members are moved outwardly with relation to the platen drum, they are moved inwardly with relation to one another. Asa consequence of the relative inward movements of the members 28, there is a relative inward movement of the plates This movement is comparatively slight but it is provided for by the provision of the slots 35 above mentioned and by the arrangement of said plates shown in Fig. 9, wherein the end of one plate is free to move past the end of an adjacent plate for a slight distance.

Each lower die 5, in addition to the die box constructed as above described, includes a die plate, as 37, to the under face of which there may be attached a bed plate, as 38. The die plate 27 moves radially, inwardly and outwardly, with relation to the platen drum, and is always disposed within the confines of the die box.

It should be here stated that in the operation of the machine, the material to be pressed into shape is admitted to a dieplate at some stage of the movement of the latter and is subsequently pressed between the same and the upper die which, during the pressing operation, enters the confines of the die box. The latteris constructed in the manner explained, 2'. c. with the lining plates, in order that there may be no interstices through which the compressed material can escape. This is a disadvantage which is incident to a number of known constructions and which detracts from the quality of the product. It is apparent that by properly adjusting the members 28, the lining plates will associate so snugly with the dies that interstices of a degree sufficient to permit of the escape of the compressed material cannot possibly be afiorded.

As was stated above, the die plates 37 have radial inward and outward movement in the die boxes. The following mechanism may be advantageously employed in connection with the particular type of machine shown for effecting this movement. To each standard 1 and 2, stationary cam. plates, as 39, are secured by suitable fastening devices. The plates 89 surround the platen drum shaft 19 and are formed on their inner faces with cam grooves 40. Each cam groove e0 has a rise 41 at one side thereof and an inset dwell 42, located some distance in advance of the use To the under face of each bed plate 38, a longitudinal bar, as 43, is secured radial movements. hen the platen drum brings a die plate under bar 43 of said die plate is alined with the dwells 42. At-this point the die plate drops by gravity, its bed plate 38 resting upon the fiat face of the platen drum and the rollers 45 being disposed in the dwells 42. It is at this time that the pressing operation takes place, and inasmuch as the die plate is being then supported upon the flat face of the platen, the latter receives all the stress and consequently there is no load upon the sup porting trunnions. After the pressing operation, the trunnions follow the outlines of the rises 41 and when they have reached the highest point of said rises, the die plates are at the outward limits of their movements. After leaving the rises, the trunnions gradually enter the circular portions of the cam grooves and the die plates are brought to a position about midway between the limits of their movements. In this position they rethe upper die, the

'ceive the plastic material which is compressed when the die plates are in their lowermost positions, and the finished products are ejected when the die plates are at the outermost limits of their movements. The invention also proposes as a novel feature thereof, the provision of means for antomatically feeding charges of material to the lower (lies as they are successively moved into relation with said means. The feeding means preferably includes, as essential elements thereof, a shaft or hopper, as 46, a movable transfer frame, as 47, and a spout, as 48, the transfer frame delivering a charge of material from the hopper to the spout and the latter conveying the charge thus (lelivered to the lower die which is then in alinement with the spout.

The transfer frame has reciprocatory movement across the bottom of the hopper and such movement is effected preferably by the following mechanism in the example shown. The shaft 16 carries at its inner end a pinion, as 49, which meshes with a pinion 50 which is provided on a transverse shaft 51. The latter is supported in hearings on the standards 1 and 2 and projects beyond the standard 1, carrying at its projecting end a plate, as 52, which has a cam groove The latter is mainly of circular form and includes a chord portion 54. The plate 52 is provided to effect the reciprocation of a cam bar as 55, which at its lower end has a roller 56 that travels in the cam groove 53. It is essential that the lower end of the cam bar 55 travel in a straight line and also that said cam bar have a limited degree of pivotal movement with relation to the said lower end as a pivotal center. Accordingly, a channel bracket, as 57, is secured to the standard 1* and includes a vertical guide portion in which the lower end of the cam bar travels, the said guide portion being of greater width than the cam bar to permit of the pivotal movement aforesaid. The cam bar is also provided at its lower end with a roller 58 which is of greater diameter than the roller 56, and travels in the guide por tion of the channel bracket. The relation of the roller 58 in the channel bracket assures of the movement of the lower end of the cam bar in a straight line.

The connections between the cam bar and the transfer frame 47 include a rock shaft,

as 59, which extends between the standards" 1 and 2, and which is operatively connected to the cam bar by a link 60, one end of the latter being fast to the rock shaft and its other end being pivoted to the upper end of the cam bar. The rock shaft 59 is pro vided with a air of upwardly extending arms, as 61, t5 the upper ends of which slotted links, as 62, are pivoted. The side bars of the transfer frame 47 are provided with trunnions 63 which project through slotted openings 64 in the walls of the hopper 46, and through the slots in the links 62.

In this connection it is preferred to have a certain degree of play between the transfer frame 47 and the links 62, in order that the latter may have some degree of initial movement prior to the movement of the frame for the purpose of allowing pauses between the reciprocatory strokes of the frame. By virtue of these intermissions between the strokes of the frame, time is allowed for the latter to eii'iciently receive and as efficiently discharge the measured charge. In view of these considerations the said links are slotted as mentioned, to accomplish the purposes forth. The length of the pauses between the strokes of the frame may be varied without regard to the speed of the machine, by increasing or decreasing the length of the slots in the links 62, and for this purpose an adjustable block, as 65, is employed, the block which the trunnions 63 project, and being provided with upper and lower pins, as 66, which project through additional slots 67 in the upper and lower portion of the links 62. One of the pins 66 of each block is provided with a lock nut 68, the purpose of which is to hold the block in any position at which it may be set. The blocks thus constitute, in effect, adjustable end walls for the slots whereby the length of the latter may be varied as required.

Under certain conditions it may be desired to lengthen or shorten the stroke of the transfer frame and for this purpose the link 60 is made in sections which are united by a turnbuckle coupling 70. Or it may be preferable to advance or set back the limits of the stroke of the transfer frame without regard to the length of the stroke as determined by the distance between these limits, and for this latter purpose the cam bar 55 may be made in sections and connected by a turnbuckle coupling 71. A third way of regulating the measure of material which is received and discharged by the transfer frame involves the regulation of the efficient size of the frame and toward this end the following construction is preferably employed. The frame, per so, is of rectangular outline and its side bars are fitted in recesses in the side walls of the hopper 46 and near the lower end thereof, as shown more particularly in Fig. The hopper is provided with a bottom plate, as 72, which is positioned between the side walls of the hopper and is vertically adjustable to increase or decrease the efficient depth of the frame. Accordingly, the bottom plate 72 is provided with depending a ngular brackets 73, having openings through which extend depending screw stems 7 4;, that are provided on the side walls of the hopper. Lock nuts, as 75, are arranged on the screw stems 7 4 and are tightened against the brackets 7 3, for the purpose of holding the bottom plate 72 in any desired position. In addition to the adjustable bottom plate 7 2 by means of which the eflicient depth of the transfer frame is regulated, an adjustable plate, as 76, is provided for the purpose of increasing or decreasing the charge receiving confines of the frame. Accordingly, the plate 76 is fitted slidably in the rear portion of the frame, and at its front end it is provided with a depending flange, as 77, which forms, in effect, an adjustable end wall for the charge receiving pocket of the frame. A forward or rearward movement of the plate 76, of course, results in moving the flange 77 toward or away from the front end wall of the frame, thereby decreasing or increasing the efficient size of the charge receiving pocket, the relation of which is shown more particularly in Fig. 4. For the purpose of effecting the adjustment of the plate 76, a screw stem, as 78, is swiveled in the end wall of the frame, and has threaded engagement in a lug 79, which depends from the plate 76. It is apparent that by turning the screw stem 78 in the proper direction, the plate 76 is moved forward or rear ard, as the case may be to decrease or increase the confines of the charge receiving pocket. In order that no interstice of any material degree may occur between the bottom plate 7 2 and the flange 77, a plate, as 80, is loosely held against the latter for vertical movement. The flange is provided with vertical slots 81 and the plate 80 is provided with screw stems 82 which project through the slots and on the ends of which securing nuts 83 are provided. It will be apparent that irrespective of the position to which the plate 7 2 is set, the plate 80 will bear thereagainst, to carry out the purpose indicated.

The operation will be readily apparent from the foregoing description. The platen' drum is intermittently rotated in a known manner, each movement thereof taking up one-fifth of a revolution. As a die box comes into alinement with the spout t8, the feeding device is operated by the means provided therefor, the transfer frame in such operation moving forwardly and carrying therewith a measured charge of material which enters the spout, as clearly shown in Fig. 1, this charge running into the die box. The die box which has been thus filled, in the next step of the movement of the platen drum, drops to a position upon the flat face of the drum, and the die box immediately in the rear thereof is filled in the manner explained. The previously charged die box which has dropped to a position upon the face of the drum, is now in alinement with the upper die, which descends into the die box and shapes the material therein to form the object designed to be produced, 6. g. a roofing tile. As was pointed out, the stress of the pressure incident to the downward movement of the upper die, is taken up by the drum and not by the die supporting bar. Inasmuch as there are no interstices through which the material can escape as a consequence of such pressure, the resultant product is of a very superior grade, being without lamination and less porous than articles ordinarily produced in this manner. In the next step of movement of the platen drum, which is subsequentto the retraction of the upper die, the lower die plate is forced outwardly in the manner explained, as clearly shown in Fig. 1. The die plate is at the limit of its outward movement when it is in a position in line with the horizontal diameter of the platen drum. .As soon as it leaves this position, it commences to retract, and at the inception of its retracting movement the finished article drops therefrom and is caught upon a pallet or equivalent device held by an attendant. The several die plates successively partake of the three movements indicated which are all that are required for the production of a finished article of superior grade. By regulating the amount of material fed in any of the ways described, the article can be made more or less porous as desired.

- hile the improvements herein described may be carried out with particular advantage in connection with such a machine as is shown in my prior patent. they are at the same time applicable to machines constructcd differently from the one herein shown. The present disclosure is, therefore, not to be regarded as putting any specific limitation, not incorporated in the claims, upon the general character of the machine employed.

Having fully described my invention, I claim:

1. In a machine for pressing plastic material, the combination with a pair of com panion dies which have arelative approaching movement, and a die box which incloses the dies when the latter are operatively related, of a lining interposed between the dies and the die box, the lining being of a construction whereby its dimensions may be regulated within certain limits, and irrespective of its dimensions within said limits, forming an uninterrupted surrounding inclosure for the dies in the operative relation of the latter.

2. In a machine for pressing plastic material, the combination with a pair of companion dies which have a relative approaching movement, and a. die box which incloses the dies when the latter are operatively related, of a lining interposed between the dies and the die box, the lining consisting of a plurality of plates adjustably movable with respect to one another whereby the ex tentof the confines of the lining may be varied, and of a construction to form, without regard to their particular adjustment, an uninterrupted surrounding inclosure for the dies in the operative relation of the latter.

3. In a machine for pressing plastic material, the combination with companion dies which have relative approaching movement, of a die box which incloses the dies when the latter are operatively related, the die box consisting of a frame having its inner faces inclined in outwardly convergent relation, a plurality of wall members movable inwardly and outwardly of the frame and secured against the inner faces thereof for sliding movement and a lining plate secured to the inner face of each wall member for sliding movement in the direction of its longitudinal axis.

at. In a machine for pressing plastic material, the combination with companion dies which have relative approaching movement, of a die box which incloses the dies when the latter are operatively related, the die box including a frame which has its inner faces inclined outwardly in convergent re lation, and a plurality of wall members movable inwardly aud outwardly of the frameand secured against the inner faces thereof for sliding movement and screws fitted in the walls of the frame and having threaded engagement with the wall members to produce the movements thereof.

In a machine for pressing plastic materiaL-the combination with a die and a material hopper, ofmeans for feeding a meas ured charge of material from the latter to the former and including a reciprocating rectangular transfer frame movable across the bottom of the hopper and a vertically adjustable hopper bottom plate disposed between the sides of the frame, and, in accordance with the position at which it is set, determining the eflicient depth of the frame.

6. In a machine for pressing plastic material, the combination with a die and a material hopper, of means for feeding a measured charge of material from the latter to the former and including a reciprocating transfer frame movable across the bottom of the hopper a plate adjustably related to the frame and having a depending flange which projects into the confines of the frame and forms a wall of the charge receiving pocket thereof, and an adjusting screw for determining the position of the plate.

7. In a machine for pressing plastic material, the combination with an upper reciprocatory pressing die, of a plurality of lower dies, each consisting of a die box and a die plate movable therein, the lower dies and the upper die having relative step-bystep traversing movements, trunnions asso-' ciated with the lower dies, plates having cam grooves in which the trunnions travel. the cam grooves having inset dwells, and means for supporting the lower dies when the trunnions enter the dwells the upper die having its pressing operation when the trunnions are positioned in the dwells.

8. In a machine for pressing plastic material, the combination with a reciprocatory upper pressing die, of a plurality of lower dies, each consisting of a die box and a die plate movable therein, the upper die entering the die box at the termination of its downward movement, means for producing relative step-by-step traversing movements of the lower dies and the upper die, and means for causing each lower die plate to descend to the bottom of its die box and to rest thereon during the pressing operation of the upper die, to move to the outer end of the die box subsequent to the retraction of the upper die from the box. and to move to a position midway of the depth of the box subsequent to its extreme outward movementand prior to the pressing operation of the upper die.

9. In a machine for pressing plastic material, the combination with a reciprocatory I pressing die, of a platen drum which has intermittent partial rotations, a plurality of lower dies assembled 011 the periphery of the drum and each consisting of a die box which receives the pressing die, and a die plate radially movable in the box, the latter having end slots and the die plate having trunnions which project through the end slots, and stationary cam plates arranged at the ends of the drum and having cam grooves which receive the trunnions, each cam groove having a circular portion, an inset dwell and a rise, the circular portions being at one side of the pressing die, the inset dwells in line therewith, and the rises at the opposite side thereof.

10. In a machine for pressing plastic material, the combination with material pressing means and a material hopper, of means for transferring material from the latter to the former and consisting of a movable transfer element which discharges measured charges of material from the hopper, and

means for operating the transfer element including a rotatable plate having a cam groove, a cam bar having at its lower end a roller which engages in the cam groove, means to cause the lower end ofthe cam bar to travel in a straight line in its reciprocatory movement and operative connections between the upper end of the bar and the transfer element.

11. In a machine for pressing plastic material, the combination with material pressing means and a material hopper, of means for transferring material from the latter to the former and consisting of a movable transfer element which discharges measured charges of material from the hopper, and means for operating the transfer element including a rotatable plate having a cam groove, a bracket having a vertical guide portion confronting the plate, a cam bar having at its lower end a roller which travels in the guide portion of the bracket and a second roller which travels in the groove, and operative connections between the upper end of the bar and the transfer element.

12. In a machine for pressing plastic material, the combination with an upper reciprocatory pressing die, of a plurality of lower dies, each consisting of a die box and a die plate movable therein, the lower dies and the upper die having relative step by step traversing movements, trunnions associated with the lower dies, and plates having cam grooves in which the trunnions travel, the cam grooves being so arranged that the lower dies are supported upon the bottoms of the die boxes during the pressing opera tions of the upper die.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ABRAHAM B. KLAY.

Witnesses CHARLES F. STOZENTACT,

D. J. CABLE. 

